Process of separating potassium and aluminum from their silicate combinations.



UNITED STATES PATENT OFFICE.

SAMUI QL PEACOCK, OF CHICAGO, ILLINOIS, ASSIGNOR TO INTE B aYQiIJIONAL AGRICUL- TUB-AL CORPORATION, OF, NEW YORK, N. L, A CORPORATIOI NEH? YORK.

vnocnss or snrm'rmo POTASSIUM AND ALUMINUM. FBdiif'i'm-xiz SILICATE 1,129,505. ll' o Drawing. i

- ing Potassium and Aluminum from Their Silicate Cmnbinations; and I do hereby de clarethe following tube a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it. appertains to make and use the same.

This invention relates to a process of separating potassium and aluminum from their silicate combinations whi le at the-same time producing carbids and nitrids of these metals which'may be utilized in the production of other compounds.

This invention has for its object the at;- tainment'bf the above results in a simple, expeditious and comparatively inexpensive manner, and to these ends consists in the novel steps constituting my process, all as will be more fully hereinafter disclosed and particularly pointed out in the claims.

In carrying out myprocess finely divide a potassium bearing silicate rock such as natural ortho-clase or microcline, hav

ing aformula such as KAlSi o andmix sium and aluminum are separated; in theform of decomposition products of the norl-ial carbids K. .C and All) That is to sav these higher carbidsdissociate into the lower carbids. such as K. .C and Al c respectively. The reactions which take place may be stated as follousz- If the reaction iscarricd out in an atni'osphere of nitrogen. free from air, then the-p0- tassium and aluminum are separated as ni- .trids such 1131 and Al N respectively;

' or sbflbo-nitrids such as KQN and -AI,Q;N respectively; or as a mixture of theseiieompolmds togetherwith some of the abo velcarbids. In this case; however, the

Specification of Letters Patent.

/ COMBINATIONS.

Patented Feb. 23, 101.1.

Application filed July 8. 19l2. Serial No. 708.277.

temperature should be raised to behvccn 1600 (I and 1800 C. The latter reactions \Yhile potassium and aluminum silicates are decomposed at the temperatures and under the conditions stated. the velocity of the reaction is greatly increased by. raising the temperature to say 1600" C. in the first through which the mixture is continuously fed, While nitrogen is admitted at the dis-1 charge end and continuously drawn through and out ofv the furnace at the feed end'ya' "acuum pump at the feed end of the furnace' being uscdto maintain the partial -pres sures at the desired values, But I prefer to maintain low partial pressures by simplyflushing the furnace at intervals during the process either with nitrogen. or with an inert or neutral gas such as hydrogen, or even with ordinary fuel or illuminating gas.

I am not as yet able to say with certainty just what atomic linkages are involved in the products actually produced, but from the presence of combined carbon and combined nitrogen (when nitrogen is presentin the furnace), and from other considerations,

I believe the normal valencies persist, and

that the above compounds are the ones pro:

duccd in the greatest quantities although lowing: 'carbon monoxid, CO; potassium carbid, K C; aluminum carbid, AI CQ: p'o

tassium nitrid, K N; aluminum nitrid, potassium carbo-nitrid. K CN aluminum nitrid, Al .C 'N,; and silica, Slo '3' .1 the temperature is high and theparare found to becarbon monoxid,; CO, and

the above nitrids, carbo-nitrids and silica.

It will be observed from the foregoing that at the comparatively low temperatures mentioned I a'rn'enabled to separate out from its associated compounds the potassium and aluminum lIl silicates and to drive-them off .in the form .of carbids. These gaseous compounds may next be burned with an excess of air in any suitable apparatus to form potassium carbonate. K.. .CO and aluminum (lxltl, A1 0,.

When the metallic nitrids are present in suliicient quantit} to render the recovery of their nitrogen profitable, they may be transferred from the furnace to an autoclave and treated with superheated steam at a pressure of say not less than five atmospheres,

when the follow-Zing reactions take place 2- In. the step of treating the furnace products witlrsuperheatcd steam the velocity of the reaction may. be controlled by regulating the pressure of the steam. At five atmospherespressure the reaction velocity is rather slow; as the pressure and therefore the temperature increases, however, the reaction ,velooity' increases in accordance with well known thermodynamic laws.

It is obvious that those skilled in thei art mayvvary the details of my process without departing from the spirit thereof, and therefore I do not wish to be limited to the above disclosure exceptas may be required by the, claims. I

This application difi'ers from my co-pending application entitled Process of decom-., Aug. 8, 1913 k0. 708,274 in that said co-pending applicaposing natural silicates filed tion is directed to the production of metallic carbo-nitrids such as the potassium and aluminum carbo-nitrids, from which ammonia-can also be made. In this'appllca.- tion, on the other hand, the temperature is not carried high enough to produce such carbo-niti-ids, in quantity, but only sulficicntly high to produce carbide, and incidently, small proportions of nitrids. In other words, the temperature used in this application is so low as not to require electric heat, the process being carried out at the temperatures furnished by h c tion of ordinary fuel.

\Vhat I claim is 1. The process of releasing potassium and aluminum from their silicate combinations and forming carbids which consists in heating a silicate containin said metals'in the presence of carbon an' in an tllln'lOSI)llt"=3 devoid of free oxygen to a temperatuw above 1200 C., substantially described.

2. The process of releasing potassium an-'1. aluminum from their silicate combination-- and forming carbids of said metals which consists in heatinga silicate containing said metals in the presence of carbon and in an atmosphere devoid of free oxygen to a temperature substantially between 1200 C. and 1400 0., substantially as described.

3. The process of releasing potassium and aluminum from their silicate combinations which consists in heating a silicate containing said metals in an atmosphere of nitrogen and in the presence of carbon to a temperature above 1200 C., substantially as described.

4. The process of releasing potassium and aluminum from their silicate combinations which consists in heating a silicate containing said metals in an atmosphere of nitrogen substantially devoid of free oxygen and in the presence of carbon to a. temperature above 1900 (1, while reducing below the normal the partial pressures of the reaction products, substantially as described.

In testimony whereof, I aiiix my signature, in presence of two witnesses,

V SAMUEL FEACOCK.

' IVitnesscs:

D. S. TOVELL, R. S. Cannon.

lot; 

